Valve-controlling mechanism for engines



(No Model.) 4 Sheets-Sheet 1.

P. R. SKIDMORE. VALVE GONTEOLLING MEGHANISM EOE ENGINES.

No. 463,845. l Panam-,Bd Nov. 24, 1891.

m crans cu.. vnnmlmo., msnwaron, n. c.

(No Model.) 4 sheets-sheen 2. l

I'. R. SKIDMORB. VALVE GONTEOLLING MECEANISM EOE ENGINES.

No. 463,845. Patented Nov.24, 1891.

4 Sheets-Sheet 3.

(No Model.)

F. R. SKIDMQRE. VALVE GONTROLLING MEGHANISM FOR ENGINES.

No. 463,845. Patented Nov. 24, 1891.

(No Model.)

P. R. SKIDMORE.

Sheets-Sheet 4.

VALVE GONTROLLING MEGHANISM EOE ENGINES.

' Padaenwd Nov. 24, 1891.

IIN TTnD STATES PATENT @Finca FREDERICK R. SKIDMORE, OF MILVAUKE, IIISCONSIN.

VALV'E-CONTROLLING MECHANISIVI FOR ENGINES.

SPECIFICATION forming part of Letters Patent No. 463,845, dated November 24, 1 891.

Application led June 29, 1891. Serial No. 397,852. (No model.)

the following is a full, clear, and exact description thereof.

My invention relates to new and useful improvements in valve-controlling mechanism for steam-engines; and it consists in the matters hereinafter described, and pointed out in the appended claims.

In the accompanying drawings, illustrating my invention, Figure 1 is a vertical section of valvecontrolling mechanism embodying my invention, the same being taken on line l l of Fig. 2. Fig. 2 is a vertical section on line 2 2 of Fig. l. Fig. 3 is a detail view of one of the parts. Fig. 4 is a view of a rocking valve with my improvements applied thereto. Fig. 5 is a horizontal section of another form of my improved valve-controlling mechanism, taken on line 5 5 of Fig. 7. Fig. 6 is a side elevation of the same, partly in section. Fig. 7 is a vertical section on line 7 7 of Fig. 5. Fig. 8 is a view of an engine with my improved valve-controlling mechanism applied thereto. Fig. 9 is an enlarged sectional view. on line 9 9 of Fig. 8. Fig. 10 is a detail view of a modiiied form of one of the parts, and Fig. Il aview of another modiiication. Y y

In Figs. l, 2, 3, and 4 my improved valve-l controlling mechanism is shown as adapted for use in connection with sin gle-acting valves of the type commonly known as Corliss valves, while Figs. 5, 6, 7, 8, 9, and 10 illustrate my device as adapted for use in connection with double-action slide-valves.

I will now describe my invention with reference to Figs. 5 to 10, in which- A indicates a'steam-engine of any desired or familiar construction, B its cylinder, and C its slide-valve, arranged within a steamchest -D and adapted to be operated in any suitable manner by means of a rock-shaft E.

As shown more particularly in Figs. 8 and 9, the slide-valve O is provided with an exi tension c, upon. the outer end of which is located a transverse shaft or rod C. Rackteeth c are provided upon said transverse shaft or rod C, and a pinion eis provided upon the inner end of rock-shaft E.

F indicates the eccentric, and f the eccentric-rod. G is ahousing revolubly supported upon the outer end of the rock-shaft E and provided with an arm g, to which the eccentric-rod f is connected. Acam H is keyed to the shaft E and is located within the housing G, said cam being provided with raised portions H H2, having notches or depressions 7L h and 71, h adjacent to its opposite faces, and with intermediate depressions h2 h3, located, respectively, between the raised portions H H2. Yokes I I are movably engaged within extensions G G2 on the housing G, the arms of said yokes being arranged in line with the raised portions H H2 of the cam H and each provided with aprojection i, said projections being adapted for engagement with ther Yare provided spiral springs j j, arranged to bear at their inner ends against the yok'es I I and at their outer ends against stops or shoulders j j upon the outer ends of spindles J J and serving to press said yokes inwardly. Rollers K K'are supported between the arms of yokes I I, as shown in Figs. 5 and 7, said rollers being mounted upon shafts k lo, which are journaled in lsaid arms of the yokes I I and extend outwardly through slots 7c 7c in the housing G and are each provided with rollers K K outside of and upon opposite sides of said housing G. The rollers K K, mounted upon the central portions of the shafts k k, are arranged to pass between the projections H H and H2 H2 upon the cam H as the housing G is rotated by the longitudinal movements of the eccentric-rodf, and the rollers K. K upon the outer ends of said y shafts are arranged to engage with the snrrod is connected with cams L L in such aman- `periphery of the cam Il.

ner that a lengthwise movementl of said rod will move said cams upon said rock-shaft in a direction lengthwise oi the said slots. Raised portions Z Z are provided upon opposite sides of each of said cams LL, said raised portions being so arranged that when the rollers K K upon the ends of either of the shafts 7.: 7u engage said raised `portions by reason of the oscillation of the housingG said shaft willbe lifted farther away from the cam ll, so as to move the ends of the arms of the yoke l out of line with the notches or depressions Zt Zt or Zt ZL in the cam H.

`Spindles c2 c2 are provided upon the ends of the transverse shaft C', which are tted with movable heads C2 C2, moving within cy-` lindrical steam-chambers C3 C3, to which steam ings, as `the crankshaft is operated the ec-` centric F will be rotated so as to give a longitudinal movement to the eccentric-rod f, which in turn imparts an oscillating or rocking `movement to the housing G about the rock-shaft E, which normally remains stationary. This rocking movement of thehousing vG carries the projections Z fi upon the arms of the yokes Il alternately into engagement with the notches ZZ ZL and ZZ 7L in the As the eccentric F moves rod f forward the arm g on the housing G will obviously be moved to the right, so as to oscillate the housing G and carry the yoke l upon the right-hand side o f said housing into engagement with the notches or depressions 71. 7l, in cam H. Now upon the further revolution of the crank-shaft and the eccentric F the rod f will be retracted, so as to oscillate the housing G in the opposite direction, when the yoke I will by its engagement with cam H operate to rock or partially rotate said cam, and with it the rock-shaft E. -ly this partial rotation of the rock-shaft E the pinion upon its inner end will by its engagement with the rack-teeth c on the transverse bar or rod C operate to move said bar or rod, and with it the slide-valve C, into the position shown in Fig. S. This movement ofthe valve C opens the steam-port at the forward end of the cylinder to take steam and places the port at the opposite end of said cylinder in communication with the exhaustport, at the same time placing the duct CZ at the rear end of the cylinder in communication with the steam-supply. As soon as the housing G has moved suliiciently in this direction to bring the rollers K K into engagement with the raised portions Z Zupon the right-hand sides of the movable or adjustable cams L L the yoke I upon the righthand side of said housing will be raised4 out of engagement with said notches ZL 7l., when steam, bearing against the head C2 at `the rear end of rod C', williustantly force said rod forward, moving the valve C at the same time into a position to cut off the steam from the forwardend of the cylinder, theport at the opposite end of the cylinder remaining in communication with the exhaustand the engine working expansively i'or the remainder of the rearward stroke of the piston. It will be understood that the valve is stopped in its movement by the piston C2 reaching the inner end of its stroke; but the pistons C2 C2 being loosely mounted upon theends of the rodand operating against the shoulders ou said rod, said rod is permitted afurther movement after the piston has reached the inner end of its strokeby means of the pinion e, rock-shaft E, and connected mechanism, so as `to admit steam at the other end of the cylinder. The valve remains stationary, however, from the time when the piston C2 reaches the inuerend of its stroke until this further movement by said valve-gear is effected. By the time the piston has completed its stroke toward the rear the eccentric F, through the medium of rodf, will have operated to rot-ate thehousing G, so as to bring the other yoke I into engagement .with the notches 7L Zt on cam Il, so that as the said eccentric passes the center said housing G will be rotated in an opposite direction from the movement above described, but in the same direction as the 1ast-described movement of the parts by the auxiliary piston C2, to move the valve C into a position to ad mit steam to the rear end of the cylinder and place the forward end of said cylinder `in communication with the exhaust, at the same time placing the duct (Z incommunication with the steam-supply. Now when the housing G has been oscillated sufficiently to bring the rollers K i into engagement with `the shoulders Z Zupon the 1eft-hand side of the cam L the yoke l will be raised out of. engagement with the notches h 7L', when the steam-pressure upon the head C2 on the end of the rod C will immediately act through the medium of said head C2 and rod C to move the valve C into a position to cut oil' the supply of steam from the rear 'end of the cylinder and at the' same time from the forward duct CZ.

It will be observed by reference to Fig. 8 of the drawings that the exhaustports c2 c2 in the chambers Cf" C3 are so arranged that as the heads C2 C2 alternately reach 'the inner ends of their respective strokes said heads IIS valve-gear is then actuated to produce a further movement of the valve to take steam at. the other end of the cylinder, when steam is again cut oi instantaneously by the release of said mechanism and the operation of the auxiliary piston.

The operation of the valve-controllin gmechanism maybe regulated so as to cause the valve to cut off at an earlier or later period in the stroke, as may be required, by means of the adjustment of the cams L L upon the rock-shaft E by a movement of the governor mechanism, so as to cause the trip mechanism to operate at any desired part of the stroke of the engine.

In the form of construction illustrated in Fig. 11 of the drawings the shaft or rod C is dispensed with, the pinion upon the end of the rock-shaft being engaged with a rack located directly upon the slide-valve, and two shorter rods M M are arranged to slide in bearings at opposite ends of the steam-chest and to engage with opposite ends of the slidevalve. The inner ends of said rods are preferably provided with heads m m, adapt-ed to t closely within sockets m m upon opposite ends of the slide-valve. Outwardly-opening spring-actuated check-valves rm2 m2 are provided in the heads m m, by means of which steam is permitted to escape from the interior of said sockets as the heads 'm m are forced into the same, and is prevented from entering the said sockets while the said parts are being drawn apart. Upon the outer ends of said rods are provided heads m3 'm3, fitted within cylinders M M adjacent to the opposite ends of the steam-chest. Duets m4 m4 communicate with said cylinders and with the interior of the steam-chest, said ducts being constantly open for the passage of steam. Intermediate headsNNare located upon said rods M M, said heads being arranged to engage with sockets N N upon the outside surface of the steam-chest.

The operation of this device is as follows: When the rock-shaft is actuated, as before described, to move the vslide-valve so as to admit steam to the cylinder, this movement of the valve will bring the socket m at one of its ends into engagement with the head m on the inner end of one of the rods M. As said parts come together the steam will pass out from the interior of the said socket through the check-valve mzin said head, and by the continued movement of the valve the until the annular flange N is engaged within A socket N', forcing the valve into a position to cut off the steam. In this position the valve and the head m upon the rod are obviously held together by steam-pressure, inasmuch as steam bears upon the entire surface of the opposite side of the valve, but is prevented by the check-valve fm2 from entering between said slide-valve and the head m. Now when the valve-controlling mechanism actuated by the eccentric is operated in the opposite direction from that before described the slidevalve will be forced away from the head m on the rod M, said rod being held from further inward movement by the engagement of the collar N with the wall of the steam-chest. By the above-described movement of the valveactuating mechanism the valve is brought into engagement with the other head m and asimilar operation of the parts at the other end ot' the steam-chest takes place. served that the collars N N, being adapted to It will be Obt closely within the recesses N N', will compress the air within said recesses and tend to check the movement of the parts toward the latter end of the stroke of the piston M,

.thereby serving to prevent any undue jar or noise in consequence ot` the surfaces coming sharply together.

In the form of construction shown in Figs. 8 and 9 the movement of the valve is cheeked at the proper instant by the admission ot steam against' one head C2 at the same time that it is cut oft from the other of said heads.

Now, referring to Figs. l to 4, inclusive, it will be observed that an arrangement of parts very similar to that shown in other tigures and hereinbefore described is employed to move the valve. In this form of construction, however, the device is adapted to operate a single-acting valve, the valve-operating device' being arranged to rotate the roekshaft E in one direction only and the steam operating to return the parts to their initial position to cut o the steam. In this form but one yokel is provided upon the housing G, and the cam H is provided with notches 71, 7L upon one side only. In this form of construction, as illustrated more particularly in Fig.

,4, a piston O is arranged in a chamber O ad- IOO IZO

O is provided at one end with a head o', fitted in one end of the chamber O. A checkvalve P is provided in the end of said chamber, and is arranged to open forthe admission of air upon a backward movement of piston O and to close outwardly upon a forward movement of said piston, so as to operate to preventatoo rapid movement of the parts. Steam is ad1nitted,as before described, through a d uct p, so as to bear against the end of the piston O. In this form of construction the trip mechanism for releasing.;` the yoke from its engagement with the cam II comprises cams Q Q, revolubly secured upon the shaft E and provided with arms q g, operatively engaged with the governor mechanism, and by which the said cams may be partially rotated about said shaft to cause the mechanism to trip at any desired portion of the stroke. In Fig. IO is illustrated a somewhat similar form ot' construction adapted for use in connection with a double-action valve comprising two oppositely-adjustable cams R R, connected with and adapted to be adjusted by the movements ofthe governor mechanism.

I would have it understood that I do not desire to limit myself to the exact form or forms illustrated in the drawings, as various 'modifications may be made in the details of construction without departure from the scope ot my original invention.

I-Iaving described my invention, what I claim as new, and desire to secure by Letters Patent of the United States, is-

I. The combination, with the cylinder and the valve for controlling the admission or exhaust of steam, of mechanism connected with the said valve and with the eccentric of the engine for opening said valve, and a piston operatively connected with and adapted to move said valve into a position to close the port, substantially as described.

2. The combination, with the cylinder and piston of a steam-engine and the valve for controlling` the admission of steam to or the exhaust ot' steam from said cylinder, of mechanism connected with said valve and operatively connected with the eccentric of the engine and arranged to operate said valve to open the port, and an auxiliary steam-chamber provided with a piston operatively coilnected with said valve and adapted to move said valve into a position to close said port,

vsubstantially as described.

5S. In a steam-engine, the combination, with the cylinder, the piston, and the eccentric thereof, of a valve for controlling,r the admission of steam to or the exhaust of steam from the cylinder, mechanism operatively connected with said valve and actuated by said eccentric to open the port, trip mechanism for disengaging said mechanism from said eccentric, and a steam-actuated piston operatively conneeted with said valve and adapted to move said valve into a position to close said port upon the release of said valve by said trip mechanism, substantially as described.

In testimony that I claim the foregoing,T I have hereunto set my hand, at Milwaukee, in the county of Milwaukee and State of lViseonsin, in the presence of two witnesses.

FREDERICK R. SKIDMGRE.

Witnesses;

.I oHN E. Wines, N. E. OLIPHANT. 

